Hydraulic valve



April 16, 1946. e. s. LIGHT 2,398,542

HYDRAULIC VALVE Filed Jan. 16, 1942 5 Sheets-Sheet l I 5 if M W 26m.

ATTORNEY April 16, 1946. G. s. LIGHT 2,398,542

' HYDRAULIC VALVE Filed Jan. 16, 1942' 3Sheets-Sheet 2 INVENTOR amzgu ATTORNEY April 16, 1946. G s. LIGHT 2,398,542

HYDRAULIC VALVE Filed Jan. 16, 1942 3 Sheets-Sheet 3 TANK INVENTOR Child/git ATTORNEY Patente d Apr. 16, 1946 UNITED STATES" PATENT .IOFFICE V nrnnamc vatvs George 8. Light, Wlnsted, Conn. Application January 16, 1942, Serial No. 420,953

4 Claims. (01. arr-9s) This 'invention relates to hydraulic valves generally, and more particularly to hydraulic valves for use in fluid pressure systems including also an object of this invention to provide a valve with a hydraulic balancing means of universal nature that does not interfere with the requirement of port size spacing or positioning.

Another object of this invention is to provide a hydraulic valve capable of converting a high speed motion of continuous rotation such as that provided by conventional prime movers into a motion of continuous oscillation. Another ob- Ject of this invention is to provide a hydraulic valvefor use in a high fluid pressure hydraulic power system which can be always in hydraulic balance to eliminate. binding between moving parts and consequent faflure of such system.

A still further object of this invention is to provide a hydraulic valve capable of providing a high rate of flow reversal in a number of high pressure hydraulic circuits, each of which includes means for operating a tool or other instrumentality. Such a valve should provide any desired time relation in and between the several circuits.

Further objects and advantages of this invention will be apparent to those skilled in the art after consideration of the following specification taken in conjunction with the accompanying drawings wherein;

Fig. 8 is a side elevation of the valve shown in p of which are shown in Fig. 9;

Fig. 9 is a cross section On line 9- -9 of Fig. '7; Fig. 10 is a crow section on line Iii-l0 of Fig. 9;

. Fig. Fig.9: Fi Fig.9:

Fig. 13 is a cross section on line l3l3 of Fig.9;

Fig. 14 is a front elevation of 12 is a cross section on line l2l2 of Fig. 15 is an end view of the rotor looking from line l5|5inFig.14;

Fig. 16 is a cross section taken on line l6-I6 of Fig. 14;

Fig. 17 is another end view of the rotor taken from line 11-11 of Fig. 14;

Fig. 18 is a cross section of Fig. 14 on line l8--i8;

Fig. 19 is a diagram illustrating the flow reversals with respect to the degrees of rotation of the valve shown in Figs. 7 to 18;

Fig. 20 illustrates the application of the valve shown in Figs. 7 to 18 to a hydraulic system for Fig. l-is an end view of a hydraulic valve including the subject-matter of this invention;

Fig. 2 is a side elevation of the valve shown in Fig- 1;

Fig. 3 is a cross section taken on line 3--3 of Fig. 2;

Fig. 4 is a cross section taken Fig.1:

on line 4-4 of operating tools Fig. 21 is a cross section of the casing of a valve embodying the principles of this invention, the ports being spaced apart at an angle other than ninety degrees; 1

Fig. 22 is an end view of the high-pressure end of the rotor adapted for use in the casing of Fig. 21; and

Fig. 23 .is an end view of the low-pressure end of the rotor shown in Fig. 22..

Figs. 1 to 6 of. the drawings illustrate a. basic form of hydraulic valve embodying the invention. The valve consists of an outer casing I provided with a supply pressure inlet port 2 having a suitable pipe connection 4 which may be connected to a source of fluid pressure such as a pump. Casing i also is provided with the fluid power connections 6, I, 8 and 9. these connections being connected to a power converting mechanism, as for-instance, a piston and cylinder for converting the fluid pressure into a desired useful motion or work. The return outlet 10 is provided for connection to the return line of the pressure source, as will be explained in more detail later on in the description. 1

Casing l is sealed at the left hand end by means of the head 13 and gasket ll secured by bolts IE or in any suitable fashion. The other end of the casing is closed by a head I! and gasket ilis a cross section on line ll-H of the rotor, parts- "l jseimed by. bolts, l ..w8ether with a st to operate a tool or other instrumentality con I 1 x b ud ga nut 28 and the packing 2| Th nected with the hydraulic motor. For purposes interior of. the casing-includes port passage sf'n, or illustration let it be that channels 31, 1 24,25 and 26, theseport passages connecting with 138, 33 and 48 each subtend an angle of 40 at the outlets 6,1, 8and 9.1. a j the circumference of the rotor and passages 23,

' The valving action of the. mechanism is accome 24, "and 28 each subtend an angle of 35 at the plished byarotonshownin 4, 5 and 6,w hich same circumference. As rotor 83 rotates, presincludes a'drive 83 extendingthrough- -the sure fluid flowis appliedrfrom the chamber 34 stufilngbox 28 and 2|, settling discs 3i and32, through the channels .31 and 39 of the rotor" togetherwith the main portion '33 of therotor 10 through port passages 23 and'25-to outlets. 3 and which actually accomplishes the valving action. 8, through 75 degrees of rotation, for instance. Chamber 34 is an inlet chamber, into. which inlet At the same time. return flow is permitted from port'2 opens and chamber 35 i's an outlet chamber inlets I and 9 through port passages 24 and 28, into which outlet port It! opens. The mainelechannels 40 and 38. return chamber 35, and outment 3301 the rotor is a solid cylindrical member let Hi. This permits motion in one direction of having the cutout channels 31, 38, 38 and 48, two double acting pistons, for example, with preschannels 31 and 39 permitting the passage of sure being applied at one end of their cylinders fluid under pressure from the inlet 2 and the inlet and oil being discharged from the other end of chamber 34 to the port passages 23, 24, 25 and 28 each cylinder. Rotation beyond this point causes in the casing I, and channels 38 and 411 permitchannels 31 and 38 of the rotor to pass beyond ting the passage of fluid from the passages 23, 24, port passages 23 and 25 so that no pressure fluid 25 and 26 to outlet chamber 35. The rotor 33 may can flow-from chamber 34. After a total of 90 be provided with bore 42 connecting the space degrees of operation the channels 31 and 38 permit to the left of disc 32 with the outlet chamber 35 the application of pressure or pressure flow to the of the valve, this being provided for preventing 25 port passages 24 and 26 and outlets l and 3, while pressure from building up in the space between at the same time the channels 38 and permit the head It and disc 32 as might be caused by permit return flow from inlets 8 and 8 through leakage or fluid under pressure from chamber portpassages 23 and 25 tochamber 35. 34. Thus, there can be no end thrust at either This particular arrangement of a casing havend of the rotor member. Disc 3lneed not be the 30 ing a number of'outlets and port passages 23, 24, full diameter or the casing bore and both discs ill 25 nd 2 together with the particular form of and 32 may be closely fitted to elements l3 and rotor provides a high speed balanced hydrauli to prevent end play, It should be noted that the dia y u ted v e in a mber f outcylindrical surfaces of the rotor 33 are fitted to a lets which m y be v ly connected with a close flt to the interior of casing I so that there common inlet chamber and a common outlet will be no flow of fluid except as permitted by c r to thereby pl y the p ng 0f the the channels and passages.- hydraulic system and still preserve hydraulic bal- One or the principal features of this inv ntion anoe between the casing and the rotor. Furtheris the arrangement of the. channels 31, 38, 39 and more, e invention as described d s n p r-- 40 curator amm channel 31 beigg op mits extremely rapid flowreversal and applicaand displaced 180m "1 -:u| 39 tion of pressure; on the lefl; d m {we phannell a It, is evident from the foregoing description ing pposed t and displaced w ap cal-n. tha-tthis inventiOrr-baslcally provides a hydraulichannel 49 t t right hand n; m, 33 cally balanced valve capable ofcreatingflow re The opposed channels at each. end ofthe rotor w'r ehvdreulicsystem opera-ting filmmalways are under the same pressure; and channels e hrd e 2 but this Valve. ns ruct- 31 and 38 are equal in area as are channels 38 and in accordance h the principl s of this in- 40; Therefore, it'is evident that there'can be no ventlon' is capable operating n a much more side thrust on the rotor which might-cause it to implicated hydra-11110 System. the lic balbind with respect to the casing and regardless of 50 and the single t and outlet chambers the amount of pressure inthe inlet chamber 34, still being feaslble- Figs- W 18 f the drawthe rotor 33 always rotates 'freely.v Av further mgs illustrate Valve for use in he hydraulic reason for the hydraulic balance thus obtained system shOWn in ThiS ure illustrates is the fact that the port passages. 23 and 25 are the fact that a single valve can be arranged to conalso directly opposite one another, as i th case trol machines or motors for performing at least with the port passages 24 and26. Th areas of hree diiferent steps in a manufacturing process. opposed port passages 23, 25 are equal an m Fig- 20 shows a, source of hydraulic fluid under tical as are passages 24 and 28 so that the areas pressure including a Supply tank Pump and of the rotor which are exposed to pressure, mclud relief valve 53, valve '53 being connected across mg the channels 38 39 and an and those tank 58 and pump 5| for absorbing whatever exposed to pressure by the port passages, are always cess pressure may occur. Valve 80, the developequal on either side of any diameter section. The t of this invention is connected to the inlet provision of common inlet and outlet chambers ,plpe and the mtlet Pipe 55 whereby flow of together with the particular rotor channels and pressure fluid is possible thmugh the Pump port passages makes possible a hydraulically bah valve 60 and tank 50. The particular work apanced high speed rotary valve which will apply paratus' shown for purposes illustration only and relieve pressure with any desired time relaincludes a feed mechanism with tion, as outlet passages 23 and 25 may be disposed valve so by Pipes 62 and The crimp mechaat any desired angle with respect to the passages 115m 35 is clmnected by P 55 and P h 24 an 26. 7 tool mechanism 68 is connected to valve 60 by pipe I For the purpose of describing the operation of 69 and p and the driver mechanism 12 is the valve it will be assumed that outlets 8, I, 8 and connected by p pe 73 and pipe 74. The two pipes 9 are connected to cylinders enclosing two double to each of the various toolmecli anisms serve alacting pistons or any other form oi hydraulic temately as pressure flow and return flow pipes motor so that pressure may be turned on and oil 75 depending on the valve position. Thus as the and- 91 together with cut-away port passages 99 valve 90 rotates, the pressure from the tank 90 and pump BI is successively applied to the various mechanism and successively relieved to cause the mechanisms to perform their intended functions. Before this operation is described in detail, it will be necessary to explain the construction of the valve 90.

The details of valve 90 are shown in Figs. '1 to 18, andthis modification of-the invention differs from that illustrated in Figs. 1 to 6 only in that it illustrates the fact that a single valve rotor employing the fundamental principles of the invention demonstrated in Figs. 1 to 6 can be combined with a rotor having the channels and ports spaced in a predetermined manner to accomplish practically any desired timing of flow reversals with predetermined time relation between said reversals to thereby control and operate a number of different tools for performing a certain number of manufacturing operations. This does not mean that the utility of this invention is confined to use for controlling manufacturing operations, as it is obvious that the valveis equally adaptable for use in connection with heat engines, as for instance, single or multi-cylinder gasoline automobile engines. More particularly, the valve can control a hydraulic system for operating the intake and exhaust valves of a gasoline engine, thereby eliminating the necessity of providing a cam shaft and related parts. A still further use for the valve embodying this invention is in a distributing system where, for instance, only the high pressure half of the valve may be used to apply and relieve pr ssure-to a series of pipes which could be used for supplying oil or other fluid to any form of mechanism requlring intermittent positive flow with a predetermined time relation between the periods of flow in each of the pipes.

Figs. 7 to 13 of the drawings illustrate the valve and arrangement of parts therein. The valve includes a rotor housing 80, the plates 82, and 82', gaskets 83, and the stumng box 81 for providing an oil seal about the shaft 95 of the rotor. End plates 92 and 92' are secured to housing 90 by means of suitable bolts 94.

Housing 90 is provided with the inlet port 90 and outlet port 9I which are connected to inlet pipe 54 and outlet pipe 55, respectively, as illustrated in Fig. 20 of the drawings. The feed 6i, shown in Fig. 20, is connected to ports 93 and 94,

the port 93 being displaced counter-clockwise from the reference plane, which is arbitrarily chosen as the vertical plane of the valve as shown in the drawings. The port 94 is displaced 90 from port 93 and 95 from the reference point, as illustrated in detail in Fig. 12 of the drawings. A hydraulic balance requires that the casing be provided with a balancing port 92 displaced 180 from port 94 and a balancing port 95 displaced 180 with respect to the port 93. Likewise, similar balancing ports must be provided at the low pressure end of the casing and connected with the ports 92 and 95 by the passages I02 and I03. Thus the pressures on the exposed areas of the rotor IIO are all equal regardless of the position of the rotor, and therefore, since the ports are respectively opposed, there is no. resultant pressure on the rotor and hydraulic balance is obtained. The crimp control illustrated in Fig. 20 receives its working pressure and return from ports 99 and 91 which are connected to the pipes 99 and 91 of Fig. 20. Fig. is a cross section on line Ill-I0 of Fig. 9 and illustrates the ports 99 and 99. Port passages 99 and 99, which are specially shaped in relation to rotor ports to .provide a predetermined time of flow as the rotor is caused to revolve, serve as passages from outlets 99 and 91 to the proper pressure or outlet chamber as the location of the rotor parts may determine. This section shows specifically the shape of the port passages 99 and 99 where they would be engaged by the rotor high pressure ports. The cut-away portion 99 starts at the point 15 displaced from the vertical and continues for 105, after which there is an interval of 15, and the cut-away portion 99 begins and continues for The casing 90 is also provided with cut-away port passages I00 and IM which provide pressure compensating areas equal to the area of portions 98 and 99 and 180 displaced with respect thereto. Thus. the pressure on the surface of the rotor is equal at all times regardless of its angular position. Fig. 13 is a section on line I3I3 of Fi 9, illustrating the shape of the cut-away portions at this cross section of the casing. This figure shows the cut-away port passages 98 and 99 at the point where the port of the rotor connecting to the low pressure chamber would engage. It will be noted in Fig. 9 that these port passages are composed of narrow and wide sections, which, in effect on their extreme sides, form passages on the low pressure side equal in space to the high pressure passages, but rotated 90. This is a simplified construction which eliminates outside passages and simplifies the rotor construction. The punch mechanism I: in Fig. 20 is connected through pipes 13 and 14 to the ports I09 and I01, respectively, which are ShOWIliin detail in Fig. 11, which is a cross section on line II-II of Fig. 9. It is to be noted that these ports are displaced axially toward the center with respect (0 to ports 93 and 94, the reason for which will become apparent in the following description. The port I 09 is displaced 35 from the vertical and the port I0! is displaced 35 from port I09.

Since it is necessary to apply pressure and return to each of the aforementioned ports, they must necessarily be connected to both the inlet and outlet sides of the valve, and therefore each of the ports 93, 94, I09 and IN is provided with passages through the casing 90 to have outlets 93', 94', I09 and I0I' in the return end of the valve. These passages may be cored through casing 80, as illustrated at I9, I02 and I03 in the drawings, or they may be in the form of pipes as I5 connected with the feed lines and to the suction side of the valve through drilled and tapped holes.

All of the ports 93. 94, I06, I01, 93', 94', I05

and I01, together with the associated balancing ports, subtend an angle of, for example, 10 at the circumference of the rotor II 0. Thus they all expose the rotor area to equal pressures. Furthermore, ports I09 and I01 are opposed by displaced portsv I04 and I05, respectively, and ports I09 and I01 are opposed by 180 displaced ports I09 and I09, respectively. Pipes III and H2 connect the balancing ports together so that ing disc II4, together with its connecting shaft Ill. The sealing. disc H4 and end plate 92', to-

. a period of dwell.

gether with rotor IIO, as shown in the drawings. form inletchamber I20 and outlet chamber I2I, as illustrated by dotted lines in Fig. 9. This rotor is similar to that shown in Figs. 5 and 6 in that it also includes at its left hand end channel portion I23 and a similar portion I24 displaced 180 therefrom, as shown in Figs. 14 and 15. At the right hand end of the rotor there are the channel portions I26 and I26 180 apart and respectively displaced 90 with respect to portions I23 and I24. These portions subtend a total angle of 70 and are so dimensioned in width that they first connect with the ports 33, 94, 93' and 94' since these ports are closer to the ends of the casing 80 than are the ports I06, I01, I06 and I0'l'. However, 75 after portion I23, for instance, opens the port 93, the point I23 reaches the port I06 to open it. All of the portions I23, I24, I25 and I26 are of the same length and of equalarea. and portion I23 is displaced 15 in a clockwise direction from the vertical, and therefore the other leading edges of the channel portions are also displaced 15 from the vertical and, in the case of portions I26 and I26, from the horizontal.

Rotor H0 is also provided with the ports I 30 and I3| which are connected to the inlet or pressure end of the casing 80. These ports are displaced, as illustrated in Figs. 15and 16, 15 from the vertical and are wide enough to subtend a 15 angle along the circumference of the rotor. Here again pressure on the rotor is equalized by providing a 180 displacement between these ports sothat the relative pressure between the rotor and the casing is equalized. Figs. 17 and 18 show the outlet or return ports I32 and I33 displaced 180 apart with respect to one another and 90 from the ports I30 and I3I. These ports I30 and I3I, I32 and I33 are in aiignmentwith the port passages 98 and 99, I00 and IN, respectively, and will apply pressure to the ports 98 and 91 in the manner to be described later.

Fig. 19 of the drawings is a graph representing a total of 180 of revolution of the rotor H0 in casing 80 and shows the intervals during which pressure and return flow act on the various tools shown in Fig. 20. Referring to Figs. 12 and 15 of the drawings, it will be seen that rotor 80 starting from rest must be rotated counter-clockof channel I23 of rotor IIO reaches the vertical plane of the valve and after five more degrees an angle of pressure through port 93 will continue for or a total of of rotation when ports 93 and 94 will both be closed by the rotor. This accounts for a total of 100 of rotation of the rotor. Port 94 in the high pressure end is placed 95 beyond vertical or from the start position of the rotor channel I23. Port 96' is similarly 110 displaced beyond the start position of channel I26. The next 10 degrees permit There is no fluid flow, but whatever pressures exist on tool 66 are maintained.

After 10 degrees of rotation, the leading edge of the channel I23 meets port 94 and permits pressure fluid now from inlet 90, chamber I2 0, through lines 63, to the tool piston of 68. At the same time, the leading edge of cut-away channel I26 meets port 93 and permits discharge return of fluid from the opposite side of the piston that actuates tool I8 through line 62, port 94, channel I25, chamber I2I, and outlet pipe 65. Thus a reversai of flow is accomplished which causes a return motion of the piston on tool I8. The pressure'flow and return flow to maintain a return motion or position of tool 68 continues for 80 degrees (this is the total of the 10 degrees opening of ports 94 and 94' and '10 degrees of channels I23 or I25). When the trailing edge of channel I23 has passed the edge of port 94, the trailing edge of I25 has passed 93, and the rotor will have rotated-180 degrees. Due to the fact that channel I24 is the same shape and 180 degrees displaced from channel I23, it will engage with ports 93 and 94, and channel I24 will engage ports 93 and 94' to duplicate the hydraulic cycle just described, and two complete identica1 cycles will result from one rotation of the rotor.

Fig. 16, together with Fig. 10, shows the eifective portions of the valve in the crimping operation. Since port I30 in rotor H0 is displaced 15 clockwise from the vertical and since the port passage 98 connected with port 96 is displaced 15 in a counter-clockwise direction, there is a total of 30 of rotation, after which port I30 applies pressure from pressure chamber I20 to the port 96 and pipe line 66 of the crimping tool 65. This pressure continues through 105. which is the arc subtended by port passage 98 at the surface of rotor IIO. In the meantime 15 of rotation is added, since port I30 subtends an angle of 15 at the surface of rotor IIO, making a total of during which pressure is applied to port 96. At the same time return flow occurs through port passage 99 and channel I32.

At degrees of rotation rotor port I30 has passed port passage 98; rotor channel I32 has passed port passage 99, so that flow or pressure direction are changed, as will be disclosed. It should be noticed that only part of port passage 98 opens to port I30, and only part of port passage 99 opens to port I32, and that during the time described the angles subtended by the exposed part of port passages 98 and 99 are the same and permit a pressure or fluid flow and return of 120. After 150 degrees of rotation the motion of crimp tool 65 is reversed as the pipe 61 is now connected through port passage 99 and channel I30 to pressure chamber I20. Return flow is now through pipe 66, port passage 98, channel I33, and chamber I2I. Flow or pressure is maintained through a period of rotation of 60 degrees, which is the sum of the angles subtended by the 15 degree port opening and the 45 degree port passage opening 98 on the low pressure side. The shape of the port passages is such that there is a pressure flow (and return) in one direction of 120 degrees and only 60 degrees in the others. Since port I3I is the same shape and degrees removed from port I30; and port I33 is the same shape and 180 degrees removed from port I32, this cycle of 180 degrees of rotation will be duplicated for the second 180 degrees of rotation of the rotor, thus accounting for two complete identica1 cycles for 360 degrees of rotation. Here again radial hydraulic balance is obtained since ports I30 and I3I are displaced 180 apart as are ports I32 and I33. Furthermore, passage 98 is opposed by the balancing passage I00 180 displaced therefrom. Passage 91 is similarly opposed by passage I0 I. The areas of opposing passhown in Fig. 11, which is a section on line I I-I I of Fig. 9. As described hereinbefore, ports I08 and III! are farther from the end than are ports 93 and 9E, and 95 of rotation must occur before channel I23 of rotor can open the port I06.-

For a distance of 60 from vertical port passage l2: does not affect port I08 and, since this Port is displaced 35 from the vertical, there must be a total of 95 rotation before pressure is applied to this port. Pressure is continued on port I06 for a total of 35 which is the sum of 25 the remaining area of channel I20 and 10 subtend by port passage I06.

There are 35 from the trailing edge of port I06 to the front edge of port I01. The effective por-' tion of channel I23 is 25, so that there will be a period of 10 before the channel makes connection with port I07. At the same time return flow is from punch 12,- through pipe 50 and passage to port 201 in the low pressure end, channel I25 to return chamber Hi. It will be noticed that port I01 is displaced 90' ahead of port I05. Channel I25 is displaced 90 ahead of channel I23, so that the time for return flow is as great as the time for pressure fiow. At the rotation of 140, channel I23 opens into port E01; channel I25 opens into port I05 this causes a reversal of fiows and pressures to the piston actuating punch 12. Pressure or pressure flow is from chamber I20 through channel E28, port I01, and pipe H; return is from pipe 13, port passage I06, channel I25, to chamber l2l. This will continue for 35 degrees, the sum of the space subtended by the face of the port 80? (15) and effective channel surface I 23 (25). This accounts for a total of 175 of rotation. There will be a period of dwelloi 5 to complete the 180 of rotation of the rotor. Because of the fact that channel I23 is 180 displaced beyond channel I24, a second and identical cycle will be made for punch I2 with a second 180 of rotation, thus completing 360 of rotation of the rotor.

It will be noticed especially in this cycle that the down position of the punch 12 will be during while the return position is 135. This is accomplished by the fact that ports I06 and I01 are displaced less than 90 and, in turn, it is necessary to locate ports I06 and I01 with cross connecting pipes I5 and passage 16, as indicated. I

Port passages 98 and 99 indicate another method of getting a similar result in relation to the crimp tool. These illustrations indicate some, but not all, of the possible variations of locating the ports.

In some applications of this invention it is desirable that the application of pressure to the operated device be timed to occur at intervals other than 90 apart in the operating cycle. Figs. 21, 22 and 23 illustrate a method of adapting the invention to such circumstances. In Fig. 21 casing i is tapped to provide ports such as 8, I, 8' and 9' which are spaced apart as illustrated. The remaining features of this modification of the valve are similar to those shown in Figs. 1 to 6 except as illustrated in Fig. 23. The rotor 33' includes a pair of channels 38' and 40' which are spaced apart by 180 in a manner similar to the rotor of Fig. 6. However, it is necessary at the low pressure end of the rotor to provide channels n, a" spaced apart by 180 and displaced clockwise from ports 38 and 40 by the same angle as there is between 0' and 9' and channels I50 and Ill also spaced apart by 180 and displaced vin a counter-clockwise direction from channels 31' and 39' by an angle equal to twice the angle between ports 8' and 1' shown in Fig. 21. Here again the principle of the invention has been applied to maintain hydraulic balance by making all ports and channels of equal areas and opposed to one another as taught hereinbefore. The operation of this modification of the valve is obvious from the description given hereinbefore in connection with Figs. 1 to 6.

From the above it is evident that this invention enables theuse of a valve having a single rotor, a single inlet port and a single outlet port for, first, feeding a piece of wire, then grasping the wire to hold it firmly in its advanced position, and then driving a, tool to punch a head on the end of the wire. Not only does this single valve enable these operations, but it also returns the tools to their normal position for a subsequent operation. This modification of the valve embodying the invention described hereinbeiore illustrates the feasibility of providing a high speed hydraulic system for performing a series of operations at predetermined time intervals. Not only is such operation feasible, but it is accomplished by a rotating valve having a single inlet port and a single outlet port, and

perfect hydraulic balance is maintained throughout the rotation of the valve.

It is not intended that this invention shall be limited to a valve embodying the specific structural details shown in the drawings, as it is obvious that there are many ways of'sealing the ends of the casing, and there are several alternative methods of providing passageways between the pressure end of the valve and the suction end of the valve. For instance, the valve casing may be cored to provide passages, or it may be merely drilled and tapped for external'pipe connections. Thus, it is intended that the valve may be constructed in accordance with well known methods. Further modifications of this invention will occur to those sfilled in the art, and therefore it is desired that this invention shall be limited only as required by the prior art and the appended claims.

What I claim is:

.1. A rotary valve comprising acasing having cally opposed ports in said plug extending into the plane of said supply port and in constant communication with the exhaust port, said casing being provided with a recess substantially similar and diametrically opposed to said supply por 2. A rotary valve comprising a casing having a substantially cylindrical-chamber therein, said casing having an inlet port, an exhaust port, and supply ports opening into said chamber, said inlet port and said exhaust port being located in planes axially removed from each other and said su ply ports being in other axially spaced planes,

a plug rotatively mounted in said chamber, pairs of substantially similar and diametrically opposed ports of said plug extending into the planes of said supply ports and in constant communication with the inlet, pairs of substantially similar and diametrically opposed ports in said plug extending into planes of said supply ports and in constant communication with the outlet, said casingbeing provided with recesses substantially similar and diametrically opposed to said supply ports.

3. A valve adapted for uniform rotation, comprising a casing, having a substantially cylindrical chamber therein, said casing'having an inlet port an exhaust port and supply ports opening into said chamber, said inlet port and said exhaust port being located in planes. axially removed from each other and said supp y ports being in other axially spaced planes, a plug rotatiably mounted in said chamber, an annular space around said plug in constant communication with the inlet port, pairs of substantially similar and diametrically opposed ports in said plug extending into planes of said supply ports and in constant communication with'said annular space, a second annular space around said plug in constant engagement with the outlet port, pairs of 4. A rotary valve comprising a casing having a substantially cylindrical chamber therein, said casing having an inlet port, an exhaust port, and supply ports opening into said chamher; said inlet port and said exhaust port being located in planes axially removed from each other and said supply ports being in still another plane, one or said supply ports comprising a circumterentially elongated portion along one of its sides and an interconnected shorter portion along its other side, said casing being. provided with a recess substantially similar and diametrically opsubstantially similar and diametrically opposed ports in said plug extending into planes ofsaid supply ports and in constant communication with said second annular space; said casing being prowided with recesses substantially similar and diummhaically-oppos'ed to said supp y P a P sage connecting an end surface or the plug and the second annular space. j

posed to said port, a second one of said supply ports also comprisinglong and short interconnected portions similar to-the first one but arranged with its short oilset portion in circumferential alignment with the long portion of the first supply port and its long portion in such alignment with the short portion. or such first supply port, said casing being provided with a recess substantially similar and diametrically opposite the second mentioned supply port, a plug rotatably mounted in said chamber, a pair of substantially similarand diametrically opposed ports in said plug, in constant communication with the inlet, and aligned circumierentially with the aligned long and short portions on one side of the supply ports, a second pair of substantially similar and diametrically opposed ports in said plug inonstant communication with the outlet and aligned circumierentially with the long and short portions on the other side of; said supply ports. 

